While men are typically more likely to develop blood clots and deep vein thrombosis, women do face one significant risk factor: birth control.
Over 200 million women worldwide take some form of birth control pills, with millions more depending on intrauterine devices, injectables, or patches as their contraceptive of choice. The pill, according to a 2010 study, has been the most popular method since 1982.
But many of these birth control methods carry a significant threat of blood clotting and deep vein thrombosis.
For example, the drug company Merck, maker of the NuvaRing, is currently paying out over $100 million in liability suits from women who say they were harmed by using the NuvaRing and weren’t adequately warned of the associated blood clot risk, according to NPR.
What do women need to know about the link between birth control and blood clots? And how can they effectively prevent pregnancy while minimizing this risk?
How Birth Control Works
Birth control pills work to prevent pregnancy through the use of hormones that imitate pregnancy in the female body.
By releasing estrogen and progesterone, these medications can “trick” a woman’s body into stopping ovulation and preventing the release of mature eggs. The estrogen works to stop the pituitary gland from producing FHS (follicle stimulating hormones) and LH (luteinizing hormone), which prevents ovulation from occurring. The progestin, meanwhile, helps make the uterine environment inhospitable to a fertilized egg while performing other actions to slow or hinder sperm’s movement inside the body.
IUDs, or intrauterine devices, use similar mechanisms to prevent pregnancy, though their applications are quite different. IUDs are inserted directly into the uterus, where they can sit for years, and release progestin to antagonize sperm, or even copper, which can act as a spermicide.
Birth control can also be ingested via a patch, also known as a transdermal contraceptive, which gradually releases estrogen and progestin to be absorbed by the wearer’s skin. From there, the mechanisms by which the patch prevents pregnancy are nearly identical to the pill. The birth control patch is usually replaced around once a week, however, whereas the pill is taken every day.
Regardless of the delivery method, these regular doses of estrogen and progestin work together to prevent pregnancy. However, in tandem, they can also increase a woman’s likelihood of developing a life-threatening blood clot.
Risks & Causes of Birth Control Blood Clots
According to stoptheclot.org, birth control pills can increase a woman’s chance of developing a blood clot about three or four times over.
The primary culprit in most birth control blood clot cases is the hormone estrogen. It’s important to note, however, that estrogen does not cause blood clots. It simply increases the user’s risk of developing one by increasing the levels of clotting factors in a woman’s body.
While the overall risk remains fairly small – only 1 in 1000 for women taking oral contraceptives – any history of thrombosis or blood clotting can make for serious risk when paired with hormone-based contraceptives.
Oral contraceptives tend to get most of the press and attention when it comes to blood clotting, but the transdermal contraceptives (the birth control patch) can actually increase the clotting risk even more. The amount of estrogen absorbed from patches can be over 60% higher than that delivered by birth control pills.
Though the issues around birth control and blood clots have been gaining exposure and awareness for years, the problem has yet to be resolved. One recent study noted that newer batches of birth control pills containing drospiernone, desogestrel, or gestodene along with estrogen carry some of the highest thrombosis risks yet.
Alternatives & Solutions
Now that you know the causes and risks associated with birth control and blood clots, here is what you can do to safely prevent pregnancy while minimizing your own risk:
First and foremost, consult your doctor and work together to choose a contraceptive plan that fits best with your lifestyle and medical history. You may prefer patches over pills, or IUDs over injectables, but be sure to account for any family history of blood clotting or any other risk factors you may carry.
Pair your birth control with an anticoagulant. Anticoagulants prevent clotting and can cancel out the effects of estrogen on your blood. Women taking anticoagulants may experience heavy menstrual bleeding, but this can be managed with the help of your doctor.
Consider progestin-only contraceptives, including pills (Micronor, Nor-Q.D., Ovrette), IUDs, or 3-month injections (Depo-Provera) to limit your exposure to estrogen that may increase your clotting factors.
Finally, if you’re taking or considering taking any sort of contraceptive, get regular screening for high blood pressure so that you can monitor your risk for clotting and thrombosis. If you’re worried you may be suffering from a blood clot as a result of taking birth control, look for these commons signs and symptoms and consult your doctor before taking any medical action.